Carbureter.



w. SCHOOF, JR. CARBURETER APPLICATION FILED MN. 28. 1909.

1,135,729. nt d 221m. 13, 1915.

A r TORNE Ys UNITED STATES PATENT OFFICE.

WILLIAM SCHOOF, J'B., OF MILWAUKEE, WISCONSIN.

CABBUBETER.

Application filed January 28, 1909.

To all whom it may concern Be it known that I, WILLIAM SOHoor, J r., acitizen of the United States, residing at Milwaukee, county ofMilwaukee, and State of Wisconsin, have invented new and usefulImprovements in Carburetors, of which the following is a specification.

My invention relates to improvements in carburoters for internalcombustion engines.

The object of my invention is to provide a mixing valve in which thequality of the gas or combustible mixture will not be materiallyaffected by variations in the speed of the engine or in the quantity ofthe mixture received by the engine cylinder and in which the supply tothe engine will be controlled both as to quantity and quality byadjusting a single valve, and no alve adjustments will be required tocontrol the supply of liquid hydro-carbon.

In the following description, reference is had to the accompanyingdrawings, in which Figure l. is a vertical sectional view of acarburetor involving my invention. Fig. 2- a sectional view drawn online zv-a2of Fig. 1. Fig. '3 is an operative, diagrammatic illustrationof one of the air inlet and one of the vapor outlet ports, the latterbeing reversed in position, with dotted lines indicating the relativeeffect of the valve upon the capacity of the two ports as it moves fromopen to closing po'sition; the air inlet port being also provided with adotted line indicating the relative capacity of the vapor outlet portwhen fully open. Fig. 4 is a detail view of the valve and its seat. Fig.5 is a detail view of the valve actuating stem. Fig. 6 is a detail viewof the crank l oscillatory stein P and spiral segment Q.

Like parts are identified by the same reference chara ters throughoutthe several news.

The valve casing A is provided with an oil inlet duct B and an air inletduct C, the mixed gases being delivered to the engine through a duct D.The oil delivered through the duct B is derivedfrom a chamber E in whichthe oil is maintained at a constant level, preferably by means of a that(-2, operatively arranged with reference to a. valve actuatinglever F,which operates to opei a spring actuated valve G controlling thedelivery of oil to the valve G from a source of supply through afiltering ehan1 Specification of Letters Patent.

Patented Apr. 13, 1915.

Serial No. 474.753.

ber G and a duct 9. A screen or filter H is preferably employed in thefiltering chamber G. A spring g normally holds the valve G to its seat,from which the valve is lifted when the float e bears upon the free endof the lever F, the admission of the hydro-carbon to the chamber E beingthus controlled by the float so that the level of the liquid in thechamber remains substantially constant.

The stem 1 of the valve G is slidingly mounted in a nut I, which may beprovided with a vent J whereby the pressure in chamber E, which also hasa vent J, remains constant.

A. cup-shaped valve seat K receives oil from the duct B through itsbase, this duct B extending longitudinally in a standard L and receivingoil from the chamber E through a series of comparatively small aperturesb in such standard. The standard passes through a central aperture inthe float e and the walls e of said aperturepreferably diverge upwardly,so that when the carbureter is used for portable engines. the float canadjust itself to the level of the liquid in the chamber E withoutbinding upon the standard.

The valve seat K is provided with a series of triangular ports K, theside walls of which converge downwardly to an apex at or near the baseof this valve seat. These ports communicate between the valve cavityand. an annular cavity M in the casing, which cavity in turncommunicates with the vapor outlet D.

A reciprocating valve N in the form of an inverted cup extendsdownwardly in the air inlet C and. telescopes within the valve seat Kwith its lower margin in manual open position in close proximity to theupper mar gins of the vapor outlet ports K. This valve is provided withair inlet ports 0, of substantially the same shape as the ports K andhaving the same dimensions when measured in the direction of valvemovement, but with the side walls of each port diverging upwardly at anangle which is slightly less than the angle of divergence of sue wallsin the port K, the difference in total capacity thus produced being suchthat the vapor outlets K have a capacity when the valve i-; fully opensuiliciently in excess of that of the air inlets to produce a suction atthe oil inlet and to secure the delivery of the requisite amount ofhydro-carbon, which,'

when vaporized, will nearly compensate for the difference in capacity inthe ports K and 0.

It will be observed that with the valve in the position illustrated inFig. 1, any movement toward closing position will cause the margin ofthe valve N to move across the triangular ports K from their largetoward their small end, and as these ports are triangular in form, thearea remaining open in any given adjustment will always be equal to thesquareof the ratio of the dis tance to be traveled by the valve fromfull open position to the total distance from full open to closedposition. It will also be observed that the upper margin of the valveseat K will simultaneously have a relative movement across the ports 0,commencing however at the apexes of the triangular openings and movingtoward the larger end of base, the closing movement for any givendistance traveled reducing the area of these ports in the square of theratio which the distance of valve travel bears to the total distance tobe traveled from full open to closed position, thus also conforming tothe above stated theoretical rule.

With the described form of the ports and the arrangement of the valve asabove Set forth, if the valve is moved one quarter of the distance fromfull open to closed position, it will close but onesixteenth of the airinlet, leaving these ports at 15/16 of their full capacity. The vaporoutlet ports, however,

will have only 9/16 of their full capacity,

7/16 of their total area having been cut off by the same valve movement.If the valve is moved half way from full open to closed position, 1/4 ofthe total area of the air inlet ports and 3/4 of the vapor outlet'portswill have been cut ofl". When the valve is closed three-quarters of thetotal distance, 9/16 of the area of the air inlet and 15/16 of the vaporoutlet area will have been cut off. I have found that with ports of suchform, they will be closed in inverse proportions, as above described,the quality of the mixture will remain substantially unchanged in allpositions of valve adjustment and the vapor delivered through the outletports K will burn uniformly with a blue flame, thus demonstrating that atheoretically perfect mixture is secured. The suction at the oil inletis regulated, not only by the withdrawal of vapor through the vaporoutlet ports, but by the proportionate admission of air at the air inletports, and I find that only by varying the relative capacity of theseports in the proportions stated, can a perfect mixture, burning with ablu flame under all adjustments, be secured.

The valve N may be conveniently actuated b means of a crank P, theswinging motion of which is transmitted to the valve through a verticalstem P, spiral segment Q and valve stem N, the latter being providedwith angular rack teeth Q engaged by the spiral se%nent Q.

he valve seat K is preferabl secured to the upper wall of the chamber lby means of a head piece R carried by the upper end of the standard L,the standard being passed throu h an aperture in the base of the valveseat and the head piece being shouldered to fit the annular mar of saidaperture. The standard passes ownwardly through the chamber E and isprovided within this chamber with a nut R adapted to clam the valve seatK and the upper wall 0 the chamber E between it and the head piece R.Packing nuts S are also preferably employed where the standard passesthrou h the lower walls of the chambers E and Another structural featuredesigned to provide for wear is that of providing the c lindricalportion of the valve with a slit the valve being bored eccentric, andcomposed of material havin sufiicient resiliency to produce an expan inpressure upon the walls of the seat K. The seat K may also be providedwith a projection t entering the slit T, whereby the valve N is keptfrom rotating.

The specific form of construction shown and described herein is notessential to my invention, it being immaterial what form of structure orarrangement of the valve, valve seat, or other parts are employed toregulate the areas of the air inlet and vapor outlet ports as hereindescribed. It will be understood, therefore, that the terms and phrasesemployed in this description and the appended claims are employed asterms of description and not of limitation, it not be; ing my intentionto exclude from the scope of m invention any mechanical equivalent for te construction shown and described.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. A carbureter comprising the combination of a walled passage, providedwith triangular air admission and mixture outlet ports and anintermediate inlet for liquid hydro-carbon, of means for closing saidports simultaneously from the bases of the triangular mixture outletports toward their apexes, and from the apexes of the triangular airports toward their bases, said port closing means traveling an equaldistance across the respective ports.

2. A carburetor comprising the combination of a walled passage, providedwith triangular air admission and mixture outlet ports and anintermediate inlet for liquid hydro-carbon, of means for closing saidports simultaneously from the bases of the triangular mixture outletports toward their apexes, and from the apexes of the triangular airports toward their bases, said port, closing means traveling an equaldistance across the respective ports, said air ports, when fully open,being of sufliciently less capacity than the mixture outlet ports, tosecure the described suction at the outlet.

In testimony wh m signature in the presence of two witnesses VVILLIAMSCHOOF, J12. Witnesses:

Lmvnnm 0. wmm, O. R. Enwnz;

